Two food bloggers from North Carolina have gathered more than 200,000 signatures in an effort to persuade food giant Kraft to remove two chemical food dye additives from the mac'n'cheese packaged meals that it sells in America.

Both ingredients, called Yellow #5 and Yellow #6, are not present in equivalent products produced by Kraft in many other countries. In some places they are replaced by other substances, such as paprika, amid some health concerns over their safety.

The two campaigners, Vani Hari of Foodbabe.com and Lisa Leake of 100daysofrealfood.com, have also recorded a video of themselves conducting a taste test between the Kraft Macaroni and Cheese sold in Britain without the additives and the product sold in the United States that contains them. In the shoot the two bloggers say that the products taste and look exactly the same and point out the risks alleged to be carried by Yellow #5 and Yellow #6.

"We have been surprised by the response. A week ago right now we had not even launched it, and now the amount of support it has got has taken us back," said Leake, 35. Hari, 33, added that they had singled out Kraft Macaroni and Cheese in order to highlight a wider issue of how ingredients banned elsewhere in the world could be found in use in food products in the United States. "We wanted to educate the American consumer and let them know what is in their food. We just picked an iconic food product to really get that message across," she said.

Kraft Macaroni and Cheese certainly fits that bill. The famous blue box – and the bright yellow cheesy pasta dish that it contains – have been a staple of American and Canadian meal times for decades. But Hari and Leake's petition points out the targeted ingredients in the American version have been banned in countries such as Norway and Austria amid claims that they can cause cancer or hyperactivity in children. A report by the Center for Science in the Public Interest has previously recommended removing Yellow #6 from the domestic market.

A Kraft spokeswoman said that the company was committed to obeying all the rules set by the Food and Drug Administration in the United States. "The safety and quality of our products is our highest priority and we take consumer concerns very seriously. We carefully follow the laws and regulations in the countries where our products are sold. So in the US, we only use colors that are approved and deemed safe for food use by the FDA," the spokeswoman said.

However, Leake said that the blogging pair would continue their campaign until Kraft stopped using the additives and replaced them with the ingredients that it already deployed in its products overseas and some brands already sold in the US. "They don't have to reformulate and re-invent the wheel. They just have to use the same formula that they do in the UK," she said.

Other campaigners have previously used petitions on similar subjects. Last year a Mississippi high school student used Change.org to lobby Gatorade to stop using a specific chemical added to its energy drinks that had been linked to possible neurological disorders. The company later said it would phase the substance out, though insisted its decision was not due to the petition – which had also attracted more than 200,000 backers.

The development also shows the potential peril and power of social media in the modern age. Last year ABC news ran stories on a beef product that was dubbed "pink slime" and saw its coverage go viral on the internet. The result was a massive collapse in sales by the firm that made the substance and a rash of lawsuits.